These tiny fiber filaments glide and float seamlessly in each of our pillows. Comfortfill are thousands of siliconized polyester fibers moving independently, creating a natural, luxurious loft. Comfortfill retains its fluffiness and loft after many uses therefore it will always retain its fullness and never cluster or migrate. Siliconized fiber provides smooth and luxurious loft, great recovery, no clumping and easy maintenance / care.